Digestibility and Nutritive Value of High Crude Protein Sake Cake

<p>A system of brewing Japanese sake by liquefaction using enzymes that hydrolyze rice starch becomes popular, high crude protein sake cake (HCP-SC) that is not suitable for food is produced. But the nutrient composition of HCP-SC is very different from sake cake (dry) listed in Standard Tables of Feed Composition in Japan (2009), and its digestibility and nutritive value in swine are unclear. Thus, the digestibility and nutritive value of HCP-SC were determined in the digestion trial. At first, the nutrient and amino acid composition of 18 sake cakes for feed was analyzed to select the test ingredient. The CP content of freeze-dried sake cakes for feed was variable (13.9～69.2%DM, average: 36.1%DM), but the amino acid content (%CP) was relatively constant. HCP-SC derived from the sake brewery that had made sake cake with highest CP in the preliminary survey was selected as the test ingredient (CP73.5%DM). The LWD crossbred pigs (9 barrows and 9 gilts, initial bodyweight: 45.6 kg) were allotted to 3 dietary treatments by weight and sex and assigned to individual pen. The experimental diets were corn-soybean meal-based diet (basal diet) and 5% or 10% HCP-SC diet that partially replaced the test ingredient in the reference diet. Titanium dioxide was used as a digestibility marker. The study consisted of a 4d adaptation period followed by a 3d collection period of feces. The digestibility of the experimental diets was calculated, then the digestibility and nutritive value of the test ingredient were determined by difference (indirect) and extrapolation method. The CP digestibility of HCP-SC was calculated as 76.0% by extrapolation method, and equivalent to the value of sake cake (dry). The DE of HCP-SC was calculated as 17.11 MJ/kgDM from its general energy (GE) and GE digestibility by extrapolation method, and slightly higher than that value of sake cake (dry).</p>